Made available in DSpace on 2016-04-29T14:23:52Z (GMT). No. of bitstreams: 1 Guilherme Felitti.pdf: 1736880 bytes, checksum: 6336b05f3293c14670a708271d9fa9e8 (MD5) Previous issue date: 2009-12-04 / The popularization of the blogs from their beginning in 1996 until today, attracting profiles of users besides enthusiasts and technology professionals, presents to us new kinds of applications of the platform that surpass the initial definitions of link filters or personal diaries on the internet. This research intends to review the main basic concepts about blogs, to indicate common points to the different platform applications. The first chapter will explore blogs under three prisms: structural, explaining the tools that the available services nowadays offer; practical, exploring which habits come from the appropriation of the tools; and the conversations, with blogs hosting dialogues highly fragmented and infinitely expansible. The second chapter will retake the classification of the blogs as a genre to indicate the necessity of seeing them as language, presenting suggestions for a model of a more precise and discerning definition. The third chapter will explore the development of the blogs in United States and in Brazil, in a comparison that intends to highlight common points and differences in their development in both countries. The fourth chapter will analyze three Brazilian case studies and it is focused in their capacities to attract and interact with their communities / A popularização dos blogues do seu surgimento em 1996 até os dias de hoje, atraindo perfis de usuários além dos entusiastas e profissionais de tecnologia, nos apresenta novos tipos de aplicações da plataforma que extrapolam as definições iniciais de filtros de links ou diários pessoais na internet. Esta pesquisa pretende passar em revisão os principais conceitos básicos sobre os blogues, para indicar pontos comuns às diferentes aplicações da plataforma. O primeiro capítulo explorará os blogues sob três prismas: o estrutural, explicando as ferramentas que os serviços atualmente disponíveis oferecem; o da prática, explorando que tipos de hábitos são desdobramentos da apropriação das ferramentas; e o das conversações, com os blogues hospedando diálogos altamente fragmentados e infinitamente expansíveis. O segundo capítulo retomará a classificação dos blogues como gênero para argumentar a necessidade de encará-los como linguagem, apresentando sugestões para um modelo de tipificação mais preciso e criterioso. Já o terceiro explorará o desenvolvimento dos blogues nos Estados Unidos e no Brasil, em comparação que pretende destacar semelhanças e diferenças em seu desenvolvimento nos dois países. O quarto capítulo analisará três estudos de casos brasileiros e é focado em suas capacidades de atraírem e interagirem com suas comunidades

Cette thèse propose des approches neuromimétiques d'identification et de commande avec des applications directes au Filtre Actif Parallèle (FAP) et au Moteur Synchrone à Aiment Permanent (MSAP). Une structure neuronale complète a été développée pour réaliser toutes les fonctionnalités d'un FAP pour compenser des harmoniques de courant. La phase instantanée et les composantes symétriques d'un système triphasé de tensions ou de courants ont été estimées avec une boucle à verrouillage de phase neuronale. L'identification des harmoniques de courant a été réalisée avec des réseaux de neurones de type Adaline opérant dans les différents repères. Plusieurs schémas de commande ont été développés pour réinjecter les courants de compensation à l'aide d'un onduleur. Ils sont basés sur des techniques neuromimétiques, sur la logique floue, ou sur leur association. Une approche neuronale a été développée pour commander une MSAP à distribution quelconque avec des contraintes prédéterminées réduisant les ondulations du couple. Elle consiste en des schémas de commande directe en couple ou en vitesse pour obtenir les courants statoriques optimaux qui donnent exactement le couple électromagnétique (ou la vitesse) désiré et qui réduisent au maximum les pertes par effet Joule. Ces commandes intègrent deux blocs neuronaux, l'un dédié au calcul des courants optimaux et l'autre pour assurer leur génération à travers un onduleur de tension. Toutes les approches neuromimétiques ont été validées par des tests de simulation et des essais expérimentaux. Des comparaisons avec les méthodes de commande classique démontrent des caractéristiques supérieures en termes de performance et de robustesse. / This thesis proposes Artificial Neural Networks (ANN) approaches for the identification and the control of an Active Power Filter (APF) and a Permanent-Magnet Synchronous Motor (PMSM). A completed neural architecture was developed for an APF for harmonic currents compensation. The instantaneous phase and the symmetrical components of a three-phase voltage or current were estimated with a neural phase Jock loop. The harmonic terms were identified by Adaline neural networks that estimate the instantaneous powers within different reference frames. Several intelligent techniques, based on neural networks, fuzzy logic or their association, were developed to control the inverter used to inject the harmonic currents phase-opposite. An original neural approach was also carried out for reducing the torque ripple of a non-sinusoidal PMSM. It consists in a direct torque or in a speed control schemes that elaborate the optimal stator currents which exactly give a desired electromagnetic torque or speed and which minimize the ohmic losses. The control schemes integrate two neural networks, one to calculate the optimal currents and one to ensure their generation through an inverter. The neural network approaches were all evaluated by simulated and experimental tests. The results confirm their excellent characteristics in terms of both performance and robustness. Comparisons with conventional methods prove their superiority.